did you check how 'flat' the new covers fit on the heads ?
( not actually sure if you reallymean new covers or just new gaskets )
in either case ...
like do they rock slightly ..like they are not flat ?

I saw others' posts about gluing them to the VC's and grease on the head
side.
I just put them on dry and they work fine usually.
I have one valve cover amoung my many that will not seal ...
it's just faultysomehow.

I'd try the old ones back on ..
swapped side-to-side.

Scott
turbovans

On 10/26/2012 4:24 PM, Don Preston wrote:
> Hi all,
>
> So, while replacing the exhaust system a couple weeks ago I also replaced the rocker covers, with new cork seals, as one of them was leaking. Thing is, now both covers have slow leaks, yay!
>
> Anyone run into this? Tried bending clips to get as tight a seal as I could, and made sure the seals are contacting properly. Ideas?
>
> Don
> '87 2.1 Vanagon GL ASI